Copper Reds

: ON THE PRIMARY, RED.

A somewhat finely coloured red oxide is produced by exposing to a white

heat for twenty minutes, a mixture of certain proportions of blue

vitriol, mono-carbonate of soda, and copper filings. The product,

however, is affected by impure air, and is otherwise not so desirable as

an iron oxide.



An interesting account has lately been given by Professor Church of a

new animal pigment, containing copper, found in the feathers of the

violet plantain-eater and two species of Turacus, natives respectively



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